Check gauges on 2002 Chevrolet Trailblazer

just noticed that my check gauges light would go on then cut off back and forth. I looked at my gauges and noticed that my oil pressure gauge will be fine then fall then jump back to normal. What do you think?

1 answer 1 comment
i would start by changing the oil pressure switch on the engine.
When I am idleing it drops , then when I give the gas it jumps back to normal ...... Is an oil pressure switch expensive usually?